1. Field of the Invention
The present invention relates to a surgical microscope system, and more particularly to a surgical microscope system having an imaging section for forming an image of an object being observed, and a display section for displaying the image formed by the imaging section.
2. Description of the Related Art
In recent years, so-called microsurgery has been performed in increasing numbers, thanks to the new surgical techniques invented and the novel surgical instruments developed. In an ophthalmological or neurosurical operation, for example, a surgeon uses a surgical microscope system having an observation optical system, to observe a magnified image of the object he or she is treating.
Most surgical microscope systems comprise a barrel which contains a microscope, and a support which supports and holds the barrel at a desired position at a desired angle.
A surgical microscope system which comprises an observation optical section and an imaging section is disclosed in, for example, Jpn. Pat. Appln. KOKAI Publication No. 3-39711. The imaging section has a light-receiving surface which is located at a focal point of the objective optical unit incorporated in the observation optical section. The imaging section generates a video signal representing an image of an object. The video signal is supplied to a display section, which displays the image of the object.
East German Patent No. 259265 discloses another type of a surgical microscope system which comprises a head-mount display or a TV monitor display for displaying an image of an object formed by an imaging section so that a surgeon may observe a left image and a right image both reflected by a mirror.
The conventional surgical microscope systems are disadvantageous in the following respects.
First, since the imaging section and the display section are contained in the barrel and located near the ocular section, the barrel is large and therefore acts as an obstacle to the surgeon who is performing an operation. If the barrel contains a monitor as well, the barrel will be considerably long, reducing the working space available to the surgeon. To provide a sufficient working space, the imaging section and the display section may be located in a separate manner--the former near the object the surgeon is treating, and the latter near the surgeon's eyes.
However, when the surgeon, who customarily moves the ocular section to another object, turns his or her head to see the other object through the ocular section, he or she cannot see an image of the other object since the imaging section does not move to the other object.
Second, an image formed by the imaging section and displayed by the display section looks whitish and is hard to see, particularly when it is too bright, due to the limited dynamic range of the display section. The adjustment ability which the human eyes possess cannot be utilized as in observing a 3D image through an ordinary stereoscopic microscope. It is necessary to adjust the view-point brightness and control the focusing, with more accuracy. To enable the surgeon to observe a 3D image, the left and right images must have the same brightness. However, the images cannot always be identical in brightness since the left and right optical paths are not arranged in a same direction. The left and right images must be adjusted in terms of brightness with high accuracy in order to provide a 3D image.
Third, a surgeon who is observing an object with a microscope and places his or her eyes on the two ocular lenses of the microscope may fail to locate the object since the object is present outside the lines of vision. If the surgeon wears a head-mount display, the object may be placed on the lines of vision, but the surgeon cannot correctly grasp the distance between him or her and the object.
Fourth, in the case of a so-called video microscope system which enables a surgeon to perform an operation on an object while seeing a magnified image of the object, the image will disappear if any electric component malfunctions or if any signal cable is cut. In such a case, the surgeon cannot continue the operation.